Significance Teasing out biochemical information from ancient organic-rich sediments, notably the timing of the emergence of photosynthesis relative to the inferred oxygenation of Earth’s atmosphere, remains a challenging opportunity. To […]
PNAS
Posted inBiosignatures & Paleobiology, Fossils & Paleontology, Habitable Zones, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography
The First Animals On Earth May Have Been Sea Sponges, Study Suggests
A team of MIT geochemists has unearthed new evidence in very old rocks suggesting that some of the first animals on Earth were likely ancestors of the modern sea sponge.
Posted inBiophysics, Biosignatures & Paleobiology, Mars, Missions & Hardware, Radiation, Robotics/Rovers/UAVs, Status Report, Tricorders & Sensors
Ultraviolet And Biological Effective Dose Observations At Gale Crater, Mars
The incident ultraviolet (UV) irradiance on the surface of Mars is strongly sterilizing and plays a critical role in atmospheric and near-surface photochemistry.
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Cryobiology, Habitable Zones, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Status Report, Water/Hycean Worlds & Oceanography
Four-million-year Marinoan Snowball Shows Multiple Routes To Deglaciation
Twice during the Neoproterozoic Era, Earth experienced runaway ice-albedo catastrophes that resulted in multimillion year, low-latitude glaciations: the Sturtian and Marinoan snowball Earths.
Posted inAstrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Origin & Evolution of Life, Panspermia, Status Report
Abiotic Origin Of Citric Acid Cycle Intermediates
The molecular framework for protometabolism—chemical reactions in a prebiotic environment preceding modern metabolism—has remained unknown in evolutionary biology. Mono-, di-, and tricarboxylic acids that comprise contemporary metabolism, such as the […]
Posted inAstrogeology, Atmospheres, Climate, Weather, Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Cryobiology, Extinction events, Habitable Zones, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Status Report, Water/Hycean Worlds & Oceanography
Hematite U-Pb Dating Of Snowball Earth Meltwater Events
The Snowball Earth hypothesis predicts global ice cover; however, previous descriptions of Cryogenian (720-635 Ma) glacial deposits are limited to continental margins and shallow marine basins.
Posted inAstrogeology, Atmospheres, Climate, Weather, Away Teams & Field Reports, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Habitable Zones, Impact events, Mapping, Geodesy, Cartography, Bathymetry, Meteorites & Asteroids, Status Report
Effect Of A Giant Meteorite Impact On Paleoarchean Surface Environments And Life
Large meteorite impacts must have strongly affected the habitability of the early Earth. Rocks of the Archean Eon record at least 16 major impact events, involving bolides larger than 10 […]
Posted inBiochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Origin & Evolution of Life, Status Report
Unraveling Abiotic Organic Synthesis Pathways In The Mafic Crust Of Mid-ocean Ridges
The aqueous alteration of the oceanic lithosphere provides significant energy that impacts the synthesis and diversity of organic compounds, which are crucial for the deep carbon cycle and may have […]
Posted inBiochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life, Status Report
Origins Of life: The Protein Folding Problem All Over Again?
How did specific useful protein sequences arise from simpler molecules at the origin of life? This seemingly needle-in-a-haystack problem has remarkably close resemblance to the old Protein Folding Problem, for […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Gaia - Planetary Perspectives, Moon, Status Report
The Length Of A Day On Earth And Its Impact On The Evolution Of Life
The Earth’s rotation has been decelerating throughout its history due to tidal dissipation, but the variation of the rate of this deceleration through time has not been established. We present […]